Brassinostroides Ameliorates the Salt Stress and Improves the Growth Attributes and Essential Oil Content of Moldavian balm

Brassinosteroids are plant steroidal phytohormones playing important roles in plant growth, development, secondary metabolite accumulation, stress responses and adaptation [۱]. Such evidence indirectly confirms the involvement of brassinosteroids, such as ۲۴-Epibrassinolide (EBL) in the development of salt tolerance [۲].This study was carried out to determine the effect of EBL applications on the some growth attributes, biochemical properties and secondary metabolite accumulation in moldavian balm (Dracocephalum moldavica L.) plants grown at different levels of salt. For this aim, four different NaCl (۰, ۲۵, ۵۰ and ۷۵ mM) and three different EBL (۰, ۲.۵ and ۵ μM) concentrations were applied to moldavian balm plants. Foliar application of EBL was applied thrice during late afternoon hours with ۷d intervals using a hand-held sprayer. All of the investigated parameters were influenced by salinity and EBL. A further reduction observed along with the elevating level of salinity in growth traits and essential oil. EBL detoxified the follow-up parameters from the salinity and significantly ameliorated them especially in ۵μM concentration. Notably, EBL could mitigate the deleterious effect of salinity by boosting the activity of antioxidant enzymes, raising total phenol, flavonoids and anthocyanin content. It was determined that ۵μM of EBL for ۲۵ and ۵۰ mM NaCl was the most suitable concentrations in terms of injury degree, growth parameters, total phenolic contents and essential oil content in moldavian balm plants.

کلیدواژه ها:

Epibrassinolid ، Essential Oil ، Total Phenol ، Flavonoids ، Dracocephalum moldavica ، Antioxidative Enzymes